Internal DOS commands are those provided internally by cmd.exe:

BREAK, CD/CHDIR, CHCP, CLS, COPY, CTTY, DATE, DEL/ERASE, DIR, EXIT, LOADHIGH, LOCK, MD/MKDIR, PATH, PROMPT, RD/RMDIR, SET, TIME, TRUENAME, TYPE, UNLOCK, VER, VOL, VERIFY.

External commands are those provided by separate executables.

Dos - Dos album - was created in 1986.

MS DOS partition is always a DOS partition.. You can not make a Non-DOS partition using DOS..

1000 is mil and there are 2 so dos mil and 1 is uno

dos mil uno

DOS is an operating system. The DOS prompt is the command line where DOS commands can be run/executed.